I don't have any direct experience with the JtS, but it sounds like it has a Press-Fit 30 bottom bracket, not BB30. The Kona web site is a bit ambiguous on this point, as it says the bike has a "Press Fit BB30" bottom bracket. If a standard BB30 doesn't fit, that's pretty good evidence as to what's really going on. The BB30 standard calls for a 42mm bottom bracket shell. The PF30 standard calls for a 46mm bottom bracket shell.